1. Field of the Invention
The present invention relates to a wire feeding mechanism and an arc processing system that employs the wire feeding mechanism.
2. Description of Related Art
There are conventionally-known apparatuses for performing arc processing such as thermal spraying and welding using a wire. For example, the apparatus disclosed in JP-A-2009-248159 includes a wire reel and a roller. A welding wire is wound around the wire reel. The roller moves in cooperation with a feed motor so as to draw the welding wire from the wire reel and feed it toward a workpiece targeted for processing.
With this type of apparatus, there are cases where there is slack in the welding wire between the roller and the wire reel when the feeding of the welding wire is started. In this case, even if the roller starts rotating, the wire reel does not rotate as long as there is slack in the wire. Then as soon as the slack is eliminated, the tension in the welding wire between the roller and the wire reel rapidly increases, and the wire reel begins to rotate. It is possible for slippage to occur between the roller and the welding wire at this time. This slippage hinders the appropriate supply of the welding wire, and has the risk of leading to a problem such as a decrease in the quality of the arc processing or an arc start failure.
In another example, JP-A-2007-518568 discloses a welding wire housing apparatus for use in an arc processing system. This welding wire housing apparatus functions as a buffer for stably supplying welding wire to a workpiece. However, this welding wire housing apparatus has a configuration in which the wire is simply held so as to have an arch, and there is still room for improvement in terms of a welding wire buffer.